估计有不止一个地方有小问题，我认为其中一个地方是第 $60$ 行 `y = lower_bound(ye + 1, ye + n + 1, y2) - ye;` 应改为 `y = lower_bound(ye + 1, ye + n + 1, y2, less<int>()) - ye;`，$x$ 要取第一个大于等于的但是 $y$ 要取第一个小于等于的，以保证 `calc()` 的正确性。
这是我的AC代码的主程序，可以参考一下：
```
int main()
{
read(n);
for (int i = 1; i <= n; i++)
read(rain[i].first), read(rain[i].second);
build(1, 1, n);
read(m);
while (m--)
{
int yeary, yearx;
read(yeary), read(yearx);
int posx = binary2(yearx), posy = binary1(yeary);
bool isx = rain[posx].first == yearx, isy = rain[posy].first == yeary;
int numx = rain[posx].second, numy = rain[posy].second;
// Three basic necessary conditions: numx <= numy; query() < numx; query() < numy.
if (isx && isy)
{
if (numx > numy)
{
fwrite("false\n", 1, 6, stdout);
continue;
}
if (posy + 1 <= posx - 1 && query(1, posy + 1, posx - 1) >= numx)
{
fwrite("false\n", 1, 6, stdout);
continue;
}
if (posx - posy != yearx - yeary)
{
fwrite("maybe\n", 1, 6, stdout);
continue;
}
fwrite("true\n", 1, 5, stdout);
continue;
}
if (isx)
{
if (posy + 1 <= posx - 1 && query(1, posy + 1, posx - 1) >= numx)
{
fwrite("false\n", 1, 6, stdout);
continue;
}
fwrite("maybe\n", 1, 6, stdout);
continue;
}
if (isy)
{
if (posy + 1 <= posx - 1 && query(1, posy + 1, posx - 1) >= numy)
{
fwrite("false\n", 1, 6, stdout);
continue;
}
fwrite("maybe\n", 1, 6, stdout);
continue;
}
fwrite("maybe\n", 1, 6, stdout);
}
return 0;
}
```
by hzlqwq @ 2023-04-29 22:42:32
猜测有可能是分类讨论的情况数多了或者少了，可以再看看。
by hzlqwq @ 2023-04-29 22:45:18